Probiotic Se prepn. of Lactobacillus bacteria was extd. with H2O and aq. solns. of lipase, protease, their mixt., Me(CH2)(11)OSO3Na, HCl and lysozyme. Both single solvent and sequentional extn. were used. The exts. were studied for Se compds. by high-performance liq. chromatog. Presence of Se-methionine and Se-methionine-Secysteine amino acids as well as Se(IV) and Se(VI) inorg. compds. in the prepn. was evidenced.